Rolling mill



W. P. WITHEROW ROLLING MILL Jan. 2 1928. 1,657,331

Filed Jan.5, 1925 2 Sheets-Sheet l W. P. WETHEROW Jan. 24, 1928.

ROLLING MILL Filed Jan. 5. 1925 2 $hee ts-Sheet 2 m N. \& /2 W INVENTOR Patented lien. 24, 1928.

UNlTED STATES PATENT OFFIQE.

WILLIAM P. XVITHEROW, OF PITTSBURGH, PENNSYLVANIA, ASSIGNOR, BY MESNE AS- SIGNMENTS, TO COLONIAL TRUST COMPANY, TRUSTEE, OF PITTSBURGH, PENN- SYLVANIA,'.A CORPORATION OE PENNSYLVANIA.

ROLLING MILL.

Application filed January 3, 1925; Serial No. 412."

The present inventionrelates broadly to the rolling mill art, and more particularly to a die rolling mill and method of operating the same, although the utility of the invention is not limited in this respect.

At the present time it is customary in the rolling mill art to drive the upper and lower rolls" either by separate driving means or by inter-gearing the samc. Where the mill is used for die rolling, the separate drive has not proven altogether satisfactory, for

the reason that variations in the speed of the two rolls inevitably throws the cone sponding matrix portions of the two rolls out of registration. For this reason, use has been made of the int-er-geared' rolls, it being customary to construct special roll stands with regard to the diameter of the rolls to be used therein, or to provide roll stands of special construction, permitting rolls of different diameters to be used therein. In order to permit this interchange of rolls While maintaining a driving relationship therebetween, it has been customary to utilize a form of gearingsomewhat similar to that disclosed in the patent to Eyson, No. 879,616 of February 18, 1908. This con struction has not been altogether satisfac tory, due largely to the backlash between the teeth, thereby permitting the matrix por tions in the two rolls to move slightly out of registration. On the other hand, the use of special mills has involved a considerable expenditure, together with an increased amount of floor space, and such mills have not been altogether satisfactory for these reasons.

I have found thatcertain ,of the objections inherent in mills of both types may be effectively obviated by providing a system of driving shafts driven by a common unit, said shafts being adapted to rotate at different speeds, and then utilizing a mill adapted to be inter-connected with'any of said shafts at will. This enables me to utilize a mill of the character referred to adapted to receive rolls of different diameters. Ordinarily, the use of rolls of different diameters has involved another. difliculty, in that each diameter of roll might require a different speed of rotation, in order to properly produce the shapes to be formed thereby. By the use of shafts rotating'at different speeds, I am enabled to obtain a number of different speeds effective for driving different rolls at different speeds. i

I have also found that the speed of the die rolls should. vary in accordance with the work being done on the billet or leader being rolled. Ordinarily, the greater the work,

the slower should be the speed, in order to exert sufficient pressure on the leader to properly fill all of the cavities. This operation, however, presents another difficulty, in that changing the roll speed, changes the length of the blank normally produced thereby. As disclosed in prior Patent 1,570,660, dated January 26th, 1926, increas ing the roll speed tends to produce a shorter blank than would normally be produced. This variation in roll speed, however, bears a definite relation to the percentage of reduction to be effected by the die rolls, the tendency toward a shorter blank increasing as the percentage of reduction increases. By the present invention, I am enabled, therefore, to obtain all ofthe advantages involved in the use of interchangeable rolls, together with a control of the length of the finished product.

Another object of the present invention resides in the provision of a mill in which the rolls are adapted to be directly intergeared, thereby eliminating intermediate rolls as heretofore utilized and their attendant backlash.

In the accompanying drawings there are shown, for purposes of illustration only, certain preferred embodiments of the present invention, it being understood that the drawings do not define the limits of my invention, as changes in the construction and operation disclosed therein may be made without departing either from the spirit of my invention or scope of my broader claims.

In the drawings Figure 1 is a top plan View of one form of mill constructed in accordance with the present invention;

Figure 2 is a horizontal sectional view through the lower part of the mill housing illustrating the supporting shoes therefor and method of moving the same;

Figure 3 is a detail View, partly in section, partly in elevation and partly broken away, illustrating a portion of the mill moving mechanism, and

Figure 4 is a diagrammatic view illustrating the manner of changing the driving gears for the rolls, whereby they may be directly inter-geared at all times.

In accordance with the present invention, a mill may be provided comprising a housing 2 mounted on shoes 3 adapted to slide longitudinally on guides a formed on a bedplate For effecting movement of the mill longitudinally of the bedplate, I have shown the housing as provided with extensions 6 spaced toreceive a nut 7 therebetween and effectively hold the same against turning. This nut at one end may bear directly against the housing, and at the other end may bear against a cross-piece 8 bolted in position on the extensions 6. Cooperatingwith the nut 7 is a feed screw 9 having at one end a bearing 10 on the bedplate 5, and at its opposite end having a bearing 11 in a tubular guide 12. This guide may be of any desired construction, supported by the housing in such manner as to extend in line with the feed screw 9 and completely enclose the same at all times to prevent injury thereto and whipping of the free end. Adjacent the bearing 10 the feed screw is provided with a gear 13 meshing with a driving pinion 14: on the armature shaft of a motor 15. By reason of this construction, it will be apparent that upon operation of the the other, the housing will be correspondingly shifted along the bedplate. \Vhen the housing has reached the desired positiun, it may be bolted in such position by bolts 16 cooperating with the guides as is customary in the art.

Located at one side of the mill is a driving unit 17, which may be in the form of an electric motor, steam engine or the l1ke, this driving unit bein adapted to drive a shaft 18, the drive pre erably being effected through gears matter be termed the high speed shaft. The high speed shaft carries a smaller gear 20 rue-hing with a large gear 21 on a second shaft 22. Due to the character of the gearing. it will be apparent that the shaft 22 rotates at a materially lower speed than the shaft 18, and this shaft is therefore hereinafter referred to as the low speed shaft. The gear 21 in turn meshes with a gear: 23 slightly larger than the gears 19 and 20, and secured. to a shaft 24. The gearing ratio is such that the shaft 24 will rotate at a speed inlrrmediate that of the shafts 18 and 22, and this shaft is accordinglyv designated the intermediate speed shaft.

liarh of the shafts 18, 22 and 24 is provided on one end with a spindle coupling 25 adapted to cooperate with a spindle 26, this spindle at its opposite end cooperating with a spindlev coupling 27 on one of the r01ls of the mill. The arrangement of the drivmotor in one direction or 19. The shaft 18 will here-' ing shafts, each with its own spindle con nection, enables the spindle 26 to be quickly uncoupled from any one of the shafts, and upon operation of the motor 15, connected to one of the other shafts. In this manner, the speed of the mill can be varied at will to ell'ect variations in the length of the blank produced, irrespective of any change in roll diameter. In like manner, it the percentage of reduction to be ell'ectedby the rolls is increased by the substitution of different rolls, a lower speed may be utilized commensurate with the results it is desired to obtain. On the other hand, if larger rolls are mounted in the housing, whereby it becomes necessary to increase the distance between the axes of rotation thereof, as understood in the art, I provide means for directly inter-gearing these rolls. In Figure 1 I have shown the upper roll shaft 28 as provided with a gear 29, this gear being dctachably carried by the roll shaft and meshing with a similar gear on the shaft of the lower roll, which is directly driven through-thecoupling 27 by the spindle 26. In Figure 4 I have diagrammatically illustrated the gear 29 as meshing with a sec ond gear 30 of the same diameter, the axes of the rolls being indicated at a. If rolls of larger diameter are substituted, it may be necessary to' separate the axes as indicated by the points I). In such case, the gears 29 and 30 will be bodily removed and new gears 31 and 32 substituted, whereby the use of intermediate gears with their accompanying backlash will be obviated.

It will be apparent from the foregoing that the present invention provides a flexible installation, enabling a single driving unit to effectively drive at different speeds, it being possible to vary the speed of the mill in accordance with the diameter of the rolls, the percentage of reduction being effected, or the length of the blank to be obtained. Furthermore, the form of drive illustrated enables the use of a driving unit 01' mini mum horsepower, and makes it possible to operate this unit at maximum efficiency at all times.

The advantages of' the present invention I arise from the provision of a rolling mill, and more particularly a die rolling mill, having means for effectively driving the same at different speeds at will from a single driving unit without changing the speed of operation of such unit.

Further advantages arise from the provision of a mill of the character referred to, together with the method of operating the same by changing the gears inter-connecting the rolls in accordance with variations'in roll diameters.

I claim 2-- 1. A rolling mill, comprising a mill stand, a driving unit, a plurality of shafts driven i of said shafts,

'nection on each of therefrom at different speeds, a spindle consaid shafts, and a spindle adapted to inter-connect the mill with any the mill stand being movable relative to the driving unit to permit of such connection, substantially as described.

2. The combination with a mill, of, a driving unit, a plurality of shafts driventherefrom at different speeds, a spindle adapted to connect said mill to any of said shafts, and means for moving the mill longitudinally to bring the same into 'cooperating relation to different of said shafts at will,

- substantially as described.

3. A rolling mill comprising a pairof intergeared rolls, a driving-unit, a plurality -of shafts driven therefrom at different the driving units speeds, and means for connecting one of the rolls to any one of the shafts, the rolls and being relatively movable to permitof such connections, substantially as described.

4. A rolling mill comprising a pair of intergearedrolls mounted in a housing, a driving unit, a plurality of shafts driven from said unit at different speeds, and means for causing relative movement between the housing and the shafts to permit the connection of one of the rolls with any of the shafts, substantially as described.

In testimony whereof I have hereunto set 1 my hand. 1

WILLIAM P. WITHEROW. 

